In heat exchangers where parallel or counter flow operation of two isolated fluids (e.g., a refrigerant and air) is used, the inlet and outlet ports of the heat exchanger for these flows are disposed inward of the extreme ends of the heat exchanger vessel. Furthermore, where these heat exchangers use internal parallel plates for performing the heat exchanging between the flows, the ends of the plates are disposed at the ends of the heat exchanger. Thus, it is very important that the extreme ends of the heat exchanger vessel, including the plate ends, need to be thoroughly sealed to maintain the isolation of the two fluids. Although end caps may be brazed, or through-welded, to the ends of the heat exchanger to provide thorough sealing, the dispersed plate ends do not provide a readily dense surface to which the end caps can seal thoroughly. Thus, there remains a need for an improved manner of thoroughly sealing the extreme ends of such heat exchangers that maintains the requisite fluid isolation, that is more resistant to internal pressure forces and that is more cost effective.